Right now, let's get to the deadly and escalating flu epidemic, causing so much misery in so much of the country right now. Linsey davis is in one of the hardest-hit cities, boston. Good morning, linsey. Reporter: Good morning, george. Masks and hand sanitizers are the front defense about fighting the flu here in boston and around the country. It's not just the flu. There's a nasty stomach bug called the norovirus that's also on the rise. The fight against this particularly nasty strain of flu is quickly becoming an uphill battle. I don't remember seeing anything like this here in 20 years. Reporter: This morning, hospitals and doctors offices are running low on flu shots and tests. This is a true national shortage. Reporter: More than 128 million vaccine doses have been distributed nationwide. But with supplies dwindling, clinics can't keep up with demand. That could be gone in 20 minutes. Reporter: Across the country, schools are reporting hundreds of students out sick. At some school systems, resort to using high-powered disinfectant to clean classrooms. Today in oklahoma, one district has even canceled classes. 25% of its students are ill. From minnesota to massachusetts, states are reporting an increasing number of flu deaths. In new york alone, more than 15,000 cases of the virus have already been reported. More than three-times the number during all of last year. Michael mayo got a flu and pneumonia shot. But neither stopped him from making a trip to the hospital. Never had to strain that hard to breathe. I was pretty close to death. Reporter: Pharmacists are also struggling to fill prescription drug orders. Right now, we're getting 24 boxes of the tamiflu capsules. But we're getting 40 or 50 prescriptions for them every day. Reporter: One doctor I spoke to says what concerns him most is the transmission of this year's flu is faster than normal. Also, they have an inundation earlier than normal. Normally they don't have this many cases until flu season peaks in late january or february. Let's get more on this from our health and medical editor, dr. Richard besser. We're learning, shortages of vaccine. Shortages of tamiflu. What do you do if you can't find it? People are trying to do the right thing, which is good. There's a website that can help you. It's called flu.Gov. It will tell you the pharmacies that have the vaccine. If they don't have tamiflu, the pharmacist can mix up a cure for your child. That should cover you. We're looking at the flu but the norovirus coming in and creating so much misery. That's a nasty stomach virus. The last thing you want on top of the flu is to get that. If you were healthy before you had the flu and you're doing well with the flu, don't rush into the emergency room or your doctor's office, because you could pick up something like norovirus. Give them a call and they can help you handle your illness that way. There's a new warning on acetaminophen, which is the ingredient in things like tylenol that so many people take. John sson & johnson, the leading maker of tylenol, lowered the dose of what you should have a day of acetaminophen to 3,000 milligrams. You may take acetaminophen for your fever. But you're taking multisymptom relievers for your symptoms, they all contain acetaminophen. If you don't read the label, you can get in trouble. And young children, don't give them any over-the-counter medications without checking with your doctor first. It can be dangerous. The leading cause of liver failure. And that can be deadly. Dr. Richard besser, thank you very much.

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